| Title |
Study on Continuous Wavelength Tuning of Narrow Band Multiwavelength Spectrum Using 1/4 Wavelength Polarization Transformation |
| Authors |
Minchan Bae ; Yong Wook Lee |
| DOI |
http://doi.org/10.5207/JIEIE.2022.36.1.015 |
| Keywords |
1/4 wave retarder; Multiwavelength filter; Narrow band; Wavelength tuning |
| Abstract |
To continuously adjust the wavelength of the narrow band transmission spectrum in a multiwavelength filter based on polarization-diversity loop configuration(PDLC), we harnessed quarter-wave polarization transformation, which was implemented by a combination of four wave retarders. The PDLC-based multiwavelength filter consists of a polarization beam splitter(PBS), two polarization-maintaining fiber(PMF) segments of the same length, one half-wave retarder(HWR), and three quarter-wave retarders(QWRs). By utilizing the filter transmittance derived through the Jones calculus, we found a combination of orientation angles of the four wave retarders, which could induce an extra phase difference φ from 0° to 360° in the narrow band transmittance function. Then the calculated transmission spectrum was obtained from the eight sets of orientation angles combination of the wave retarders, which were selected to make φ vary from 0° to 315° at intervals of 45°. Theoretical prediction results on the continuous wavelength adjustment of narrow band multiwavelength spectrum using quarter-wave polarization transformation were also experimentally validated. |